With the sudden rise of world interoperability for microwave access (WiMax) technology, in order to keep its competitiveness in the field of mobile communication, the 3rd generation mobile communication system must improve its network performance and reduce network construction and operation cost. Therefore, the standardized work group of the 3rd generation partnership project (3GPP) is currently studying the evolution of the packet switch core (PS core) network and the universal mobile telecommunication system radio access network (UTRAN). That research subject is called as the system architecture evolution (SAE), and the object is to enable the evolved packet core (EPC) network to provide a higher transmission rate and a shorter transmission delay time, to optimize grouping, and to support the mobility management among the Evolved UTRAN (E-UTRAN), UTRAN, the wireless local area network (WLAN) and other non-3GPP access networks.
The current framework of the SAE is shown in FIG. 1, wherein the network elements included in the evolved universal terrestrial radio access network (E-UTRAN) is an evolved NodeB (eNodeB) used for providing the radio resource to the user access; the packet data network (PDN) is a network providing the service to the user; the EPC provides a lower delay, and allows the access of more wireless access systems, which includes the following network elements:
The mobility management entity (MME) is a control plane function entity, is a server storing the user data temporarily, and is responsible for managing and storing the context (such as: the user identifier, the mobility management state, and the user security parameter, etc.) of the user equipment (UE); allocates a temporary identifier for the user; when the UE resides in the tracking area or this network, MME is responsible for authenticating this user; processes all messages of the non-stratum layer between the MME and the UE; and triggers the paging in the SAE. The MME is the mobility management entity of the SAE system, and in the universal mobile telecommunication system (UMTS), the mobility management entity is a serving general packet radio service (GPRS) support node (SGSN).
The serving gateway (SGW) is one user plane entity and is responsible for the data routing processing of the user plane, terminating the downlink data of the UE in the idle (ECM_IDLE) state, and managing and storing the SAE bearer context of the UE, such as the IP bearer service parameter and the routing information within the network, etc. The SGW is the anchor point of the user plane within the 3GPP system, and one user only can have one SGW at one moment.
The PDN Gateway (PGW) is a gateway which is responsible for the UE accessing the PDN and for allocating the user IP addresses, and the PGW also is the mobility anchor point of the 3GPP and the non-3GPP access systems. The function of the PGW also includes policy implementation, and charging support. The user can access a plurality of PGWs at the same moment. The policy and charging enforcement function (PCEF) also resides in the PGW.
The policy and charging rules function (PCRF) is responsible for providing the policy control and the charging rules to the PCEF.
The home subscriber server (HSS) is responsible for permanently storing the user subscribed data, and the content stored by the HSS includes the international mobile subscriber identification (IMSI) of the UE and the IP address of the PGW.
Physically, the SGW and the PGW may be combined, and the EPC system user plane network elements include the SGW and the PGW.
The narrow definition of the M2M is the machine to machine communication. The general definition is the networked application and service which takes the intelligent interaction of the machine terminal as the core. It is based on the intelligent machine terminal, takes a plurality of communication modes as the access means, provides the informatization solution for the customer, and is used for meeting the informatization demands of the customer in the respects, such as monitoring, command and scheduling, data acquisition and measuring, etc.
The development of the wireless technology is the important factor of the development of the M2M market, which breaks the space-time restriction and the region obstacle of the traditional communication mode, makes the enterprise and the public get rid of the constraint of the cable, lets the customer control the cost more effectively and reduce the mounting cost, and facilitates the use. In addition, the increasing demand promotes the continuous development of the M2M, but the contradiction with the constant increasing of the information processing capability and the network bandwidth is that the information acquisition means far fall behind. While the M2M meets this demand of people very well, and people can monitor the external environment in real time through it, realize the large range and automatic information acquisition. Therefore, the M2M can be applied in the industry application, the family application and the personal application, etc. The industry application includes: traffic monitoring, the alarm system, marine rescuing, the dispenser, and driving payment etc. The family application includes: automatic meter reading and temperature control, etc. The personal application includes: life detection and remote diagnoses etc.
The communication object of the M2M is machine to machine or people to machine. The data communication among one or more machines is defined as the MTC, and in this case, it seldom needs the man-machine interaction. The machine participating in the MTC is defined as the MTC equipment. The MTC equipment is the terminal of the MTC user, which can communicate with the MTC equipment and the MTC server through the public land mobile network (PLMN). The mobile equipment (ME) is the additional function block of the MTC equipment, and that function block is used for the MTC equipment accessing the EPS system. The MTC server manages and monitors the MTC equipment. FIG. 2 is a schematic diagram of an ME accessing the EUTRAN through an EPS in the related art.
Since the MTC equipments are mostly specific application equipment, for example, the automatic meter reading and life detection use different equipments, etc. The MTC equipments of different applications have different characteristics, for example, the elevator equipment such as the lift etc. has low mobility and the packet switch only (PS only) attribute. While the monitoring and alarm equipment, besides having low mobility and the PS only characteristics, also has the attributes, such as low data transmission and high usability. Therefore, performing different system optimizations to the MTC equipment of different applications can perform management, controlling and payment, etc., to the MTC equipment.
One kind of MTC application communication is controlled by time, that is, it allows the MTC device accessing the network or performing the data sending and receiving in a plurality of particular periods, and it should restrict the MTC device from performing the above-mentioned operations beyond the permission period. In the current LTE network, when the UE needs to register in the network, or initiate a location update, or initiate a service request, the MME performs the access control to it, and then the S-GW and the P-GW are responsible for the user data transmission, however, in the related art, the MME, the S-GW and the P-GW do not adopt the mechanism to control the UE to allow accessing the network and performing communication only in the particular period. While the introduction of the M2M communication, especially the particularity of the MTC device (such as low data amount, the MTC device without the human being operation), requires that the MTC device should access the network for communication in a plurality of particular periods. The current LTE network cannot meet such a demand.